// flex 布局复用
@mixin flex($hov: space-between, $col: center){
    display: flex;
    justify-content: $hov;
    align-items: $col;
}
// 背景图格式复用
@mixin bgImg($w: 0, $h: 0, $img: '', $size: contain){
    display: inline-block;
    width: $w;
    height: $h;
    background: url($img) no-repeat center;
    background-size: $size;
}
@mixin position($pos:absolute, $top:0, $left:0, $w:100%, $h:100%){
    position: $pos;
    top: $top;
    left: $left;
    width: $w;
    height: $h;
}
@mixin positionImg($pos:absolute, $top:0, $right: 0,$w: 0, $h: 0, $img: ''){
    position: $pos;
    top: $top;
    right: $right;
    width: $w;
    height: $h;
    background: url($img) no-repeat center;
    background-size: contain;
}